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  xmlns:dei="http://xbrl.sec.gov/dei/2026"
  xmlns:ffd="http://xbrl.sec.gov/ffd/2026"
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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000061004</identifier>
        </entity>
        <period>
            <startDate>2026-06-05</startDate>
            <endDate>2026-06-05</endDate>
        </period>
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    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000061004</identifier>
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        <period>
            <startDate>2026-06-05</startDate>
            <endDate>2026-06-05</endDate>
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    <context id="offrl_2">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000061004</identifier>
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                <xbrldi:typedMember dimension="ffd:OfferingAxis">
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        <period>
            <startDate>2026-06-05</startDate>
            <endDate>2026-06-05</endDate>
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    </context>
    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="Shares">
        <measure>shares</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-356">S-1</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-357">S-1MEF</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-358">EX-FILING FEES</ffd:FeeExhibitTp>
    <ffd:RegnFileNb contextRef="rc" id="ixv-359">333-295925</ffd:RegnFileNb>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-360">0000061004</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-361">LGL GROUP INC</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="rc" id="hiddenrcOffsetTableNa">N/A</ffd:OffsetTableNa>
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    <ffd:FormTp contextRef="rc" id="ixv-398">S-1</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-399">LGL GROUP INC</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-400">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-401">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_1" id="ixv-402">Common Stock</ffd:OfferingSctyTitl>
    <ffd:Rule457oFlg contextRef="offrl_1" id="ixv-403">true</ffd:Rule457oFlg>
    <ffd:AmtSctiesRegd
      contextRef="offrl_1"
      decimals="0"
      id="ixv-404"
      unitRef="Shares">10000</ffd:AmtSctiesRegd>
    <ffd:MaxOfferingPricPerScty
      contextRef="offrl_1"
      decimals="2"
      id="ixv-405"
      unitRef="USD">6.90</ffd:MaxOfferingPricPerScty>
    <ffd:MaxAggtOfferingPric
      contextRef="offrl_1"
      decimals="2"
      id="ixv-406"
      unitRef="USD">69000.00</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate
      contextRef="offrl_1"
      decimals="7"
      id="ixv-407"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_1"
      decimals="2"
      id="ixv-408"
      unitRef="USD">9.53</ffd:FeeAmt>
    <ffd:PrevslyPdFlg contextRef="offrl_2" id="ixv-409">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_2" id="ixv-410">Other</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_2" id="ixv-411">Subscription Rights to Purchase Common Stock</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="offrl_2" id="ixv-412">true</ffd:FeesOthrRuleFlg>
    <ffd:AmtSctiesRegd
      contextRef="offrl_2"
      decimals="0"
      id="ixv-413"
      unitRef="Shares">10000</ffd:AmtSctiesRegd>
    <ffd:MaxAggtOfferingPric
      contextRef="offrl_2"
      decimals="2"
      id="ixv-414"
      unitRef="USD">0.00</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate
      contextRef="offrl_2"
      decimals="7"
      id="ixv-415"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_2"
      decimals="2"
      id="ixv-416"
      unitRef="USD">0.00</ffd:FeeAmt>
    <ffd:TtlOfferingAmt contextRef="rc" decimals="2" id="ixv-417" unitRef="USD">69000.00</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-418" unitRef="USD">9.53</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-419" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-420" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-421" unitRef="USD">9.53</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-422">(a) Pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"), the shares of common stock, par value $0.01 per share ("Common Stock"), of The LGL Group, Inc. (the "Registrant") being registered hereunder include such indeterminate number of shares of Common Stock as may be issuable as a result of stock splits, stock dividends, or other distribution, recapitalization or similar events.

(b) Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(o) under the Securities Act and assumed an offering price of $6.90 per share.

(c) The transferable subscription rights and the shares of Common Stock issuable upon exercise thereof being registered hereunder are in addition to the transferable subscription rights and the shares of Common Stock issuable upon exercise thereof previously registered by the Registrant pursuant to the Registrant's Registration Statement on Form S-1 (File No. 333-295925).
</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="offrl_2" id="ixv-423">Pursuant to Rule 457(g) under the Securities Act, no separate registration fee is payable with respect to the transferable subscription rights being offered hereby since such subscription rights are being registered in the same registration statement as the shares of the Registrant's Common Stock underlying such subscription rights.</ffd:OfferingNote>
</xbrl>
